What is the treatment for sinusitis?

Treatment of Sinusitis

Acute Bacterial Sinusitis

Amoxicillin is the first-line antibiotic for uncomplicated acute bacterial sinusitis in both adults and children, prescribed for 10-14 days. 1

When to Start Antibiotics

Antibiotics are indicated only when specific criteria are met to avoid overdiagnosis and unnecessary treatment: 2, 1

• Persistent symptoms: Nasal congestion, purulent rhinorrhea, or cough lasting 10-14 days without improvement 2, 1
• Severe presentation: High fever (≥39°C) with purulent nasal discharge, facial pain or tenderness, and periorbital swelling for 3-4 consecutive days 2, 3
• Worsening course: Initial improvement followed by symptom deterioration 3

Antibiotic Selection Algorithm

First-line therapy: 2, 1

• Amoxicillin (standard dose) for 10-14 days
• Alternative for penicillin-allergic adults: Trimethoprim-sulfamethoxazole 2

If no improvement after 3-5 days, switch to: 2, 1

• High-dose amoxicillin-clavulanate (90 mg/kg amoxicillin component, not exceeding 2g every 12 hours)
• Cefuroxime, cefpodoxime, cefprozil, or cefdinir 2
• For true penicillin allergy: Macrolides or quinolones 2, 3

For persistent failure after 21-28 days: 2

• Broader-spectrum agents with or without anaerobic coverage (clindamycin or metronidazole)
• Consider CT imaging if not already obtained 2
• Evaluate for nasal polyps, anatomic obstruction, or noncompliance 2

Adjunctive Therapies for Acute Sinusitis

Intranasal corticosteroids may be added to antibiotics, though evidence is modest: 2

• Reasonable adjunct when patient fails initial treatment, demonstrates marked mucosal edema, or has nasal polyposis 2
• Short-term oral corticosteroids can be considered in these scenarios 2

Supportive measures (all patients should receive education on): 2

• Adequate hydration and rest
• Warm facial compresses and steamy showers
• Sleeping with head elevated
• Analgesics as needed
• Avoidance of cigarette smoke and relevant allergens 2

Chronic Sinusitis (≥8 weeks duration)

Intranasal corticosteroids are the primary first-line therapy for chronic sinusitis, NOT antibiotics. 1, 4

Evidence Against Routine Antibiotic Use

The European guidelines (EPOS 2020) demonstrate that amoxicillin-clavulanate shows no statistically significant benefit compared to other treatments in chronic rhinosinusitis without nasal polyps. 4 This represents a critical distinction from acute sinusitis management.

Recommended Treatment Approach

Primary therapy: 1, 4

• Intranasal corticosteroids (e.g., fluticasone propionate, mometasone furoate) as mainstay treatment 1, 4
• Daily high-volume saline irrigation 1

Reserve antibiotics only for: 4

• True acute bacterial superinfection with systemic symptoms (high fever, severe facial pain, periorbital complications)
• When used: Amoxicillin-clavulanate 875/125 mg twice daily for 10-14 days or until symptom-free for 7 days 4

For nasal polyps: 1

• Short course of systemic corticosteroids
• Alternative: Doxycycline 1

Chronic hyperplastic eosinophilic rhinosinusitis: 2

• Does not respond to antibiotics
• Systemic corticosteroids should be considered 2

When to Pursue Further Evaluation

Recurrent sinusitis (≥3 episodes/year) requires assessment for: 2, 1

• Allergic rhinitis: Test for IgE sensitization to inhalant allergens 2
• Anatomic abnormalities: Septal deviation, middle turbinate abnormalities, accessory structures blocking drainage 2
• Immunodeficiency: Measure quantitative IgG, IgA, IgM levels and specific antibody responses to tetanus toxoid or pneumococcal vaccine 2
• Consider gastroesophageal reflux disease (GERD) as contributing factor 2

Specialist consultation indicated when: 2

• Sinusitis refractory to usual antibiotic treatment
• Recurrent episodes despite appropriate management
• Associated with unusual opportunistic infections
• Concomitant chronic otitis media, bronchial asthma, recurrent pneumonia, or immunodeficiencies 2

Surgical Considerations

Functional endoscopic sinus surgery may be indicated for: 2, 1

• Medically resistant sinusitis with localized persistent disease in the ostiomeatal complex 2, 1
• Obstructing nasal polyps after appropriate medical therapy including oral corticosteroids 2
• Significant anatomic obstruction (septal deviation compressing middle turbinate, middle turbinate deformity) 2

Critical Pitfalls to Avoid

Overuse of antibiotics: The most common error is prescribing antibiotics for viral upper respiratory infections or chronic sinusitis without bacterial superinfection. 2, 1 Symptoms must meet the 10-14 day persistence threshold or severe presentation criteria before antibiotics are warranted.

Inadequate treatment duration: Patients must complete the full 10-14 day course to prevent relapse and resistance. 1

Failure to address underlying factors: Chronic or recurrent sinusitis will persist without treating allergic rhinitis, anatomic abnormalities, or immunodeficiency. 2, 1 These require concurrent management, not just repeated antibiotic courses.

Misclassification of chronic sinusitis: Chronic sinusitis (≥8 weeks) is fundamentally different from acute bacterial sinusitis and requires intranasal corticosteroids as primary therapy, not prolonged antibiotics. 1, 4